Currently there is no specific journal for such a topic. From my experience, I can tell that I have read the most interesting geometric design articles in Transportation Research Record and Journal of Transportation Engineering (now 'Part A: Systems'). However, these journals have relatively low impact factors compared to others so your target journal depends on what you are looking for.
Thanks again for your answers. I was looking for a journal to read. The background is that I find some of the papers available through ResearchGate difficult to understand, and I was hoping for a journal which would keep me up to date with the latest ideas and research, but in a more digestible form. I checked the websites I found for the four journals mentioned, and they all seem to be directed towards academia. Maybe I should rather have asked a more basic question,e.g. "how can a non-academic keep up to date with developing theories in highway geometric design?"
Journal of road engineering https://www.sciencedirect.com/journal/journal-of-road-engineering
Journal of Highway and Transportation Research and Development https://ascelibrary.org/journal/jhtrcq
Transportation Research Record https://journals.sagepub.com/home/TRR
Journal of Transportation Engineering, Part A: Systems https://ascelibrary.org/journal/jtepbs